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TR2/3/3A New wire harness

tinman58

Jedi Knight
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After too many wiring problems I have decided too replace the whole thing. Any advice where to start ?
 
My best advice is to make sure you really need one. Very few harnesses really need to be replaced. I would replace one only if the insulation is burned, crumbling, or otherwise failing. The wire underneath is probably fine, as is the insulation under the wrap.

Most electrical problems are at connections. Replacing the harness will replace the connectors on the harness, but the tarnished or corroding mating connectors are still there, causing trouble. There are all kinds of automotive electrical connectors available. Replace those god-awful bullet connectors with something reliable, replace any bits of wire that are in bad shape, solder and use heat-shrink tubing for insulation. I think you will be way ahead of the game.
 
I would rate this as a big job when doing this in a complete car. I have done 3 in complete restorations. Where it gets difficult is under the dash. Even with a very good wiring diagram I believe it is best to label each wire end( that is the old harness and the new harness) and the exact screw or location where that wire goes. I used color coded plastic ties instead of labels.
Under the dash there is not enough room to leave the old harness in place and introduce the new one. I found starting the new harness installation with the under dash larger trunks and the 2 through the firewall ( going forward) parts. Note removing the heater is highly advisable.
I ran the various longer harness parts out prior to any connecting.
Charley
 
This is open heart surgery(IMHO) as the heater assy needs to come out too.
Take this opportunity to cherry out this bugger at this time.I recommend the silicone hoses
from BPNW. I also recommend wiring armor which easily slips over the harness for greater
protection from chafing. Resheeth the metal tabs with heat shrink tubing too.
Mad dog
 
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